1. Field of the Invention
The present invention relates generally to a vehicle detection system and more specifically it relates to a vehicle presence detection system for effectively detecting the presence of a vehicle in a location based upon a measured radio wave signal strength by a receiver.
2. Description of the Related Art
Any discussion of the related art throughout the specification should in no way be considered as an admission that such related art is widely known or forms part of common general knowledge in the field.
In areas of high traffic density where parking is at a premium, it is often times difficult to find an available parking space. The driver of a vehicle wastes valuable time and becomes frustrated while driving around a parking lot to find a parking space. The additional searching for a parking space also compounds traffic congestion and has a negative impact on the environment by the extended operation of the vehicle.
To assist drivers in locating a parking space, conventional occupancy indicators have been recently developed that indicate whether an individual parking space is available. Conventional occupancy indicator systems are comprised of a visual indicator (e.g. a light) that is mounted in each individual parking space (typically to the ceiling or wall of an indoor vehicle parking structure) and a sensor that detects the presence of a vehicle within the individual parking spot. The occupancy indicator is directly wired to the sensor to allow for communications from the sensor to the occupancy indicator. The occupancy indicator and sensor are further wired to a central parking management system that communicates with the devices and also provides electrical power to the devices.
Sensors for vehicle detecting in parking spaces have also been known in the art for the purpose of guiding traffic or enforcement. Conventional sensors for detecting the presence of vehicles include infra-red systems, magnetometer systems, image processing systems and inductive loops. The problem with infra-red systems is that they rely upon a translucent window through an enclosure that is prone to damage or blockage rendering the infra-red system useless. The problem with magnetometer systems is that they use disruptions in the earth's magnetic field caused by the presence of a vehicle which can be small and unpredictable along with being temperature dependent resulting in a low level of detection accuracy. The problem with image processing systems is they are complicated making them prone to errors. The problem with inductive loops is they are impractical to install and are unreliable so they are often times used for entry and exit points as opposed to individual parking spaces.
Because of the inherent problems with the related art, there is a need for a new and improved vehicle presence detection system for effectively detecting the presence of a vehicle in a location based upon a measured radio wave signal strength by a receiver.